Coil-spring assembly



Sept. 14, 1965 M. LEVINE 3,205,513

COIL-SPRING ASSEMBLY Filed March 17, 1964 INVENTOR.

j Zy 4 Mad 90m ATT'YS United States Patent 3,22%,513 COIL-SPRINGASSEMBLY Mac Levine, 474 Salisbury St., Worcester, Mass. Filed Mar. 17,1964, Ser. No. 352,493 7 Claims. ('(Il. -267) This invention pertains tospring assemblies of the kind employed as the resilient filling inmattresses, cushions, chair seats, or the like. Such a spring commonlycomprises a lurality of parallel rows of juxtaposed coiled springs, thesprings of one row being substantially aligned with the correspondingsprings in the next row and the juxtaposed springs in one row being tiedto the corresponding juxtaposed springs in the next row. The presentinvention constitutes an improvement upon the spring assembly disclosedin Patent No. 2,197,131, granted to David I. Levine, under date of April16, 1940.

In recent years there has developed a demand for spring assemblies ofthe above type which provide a firmer support than was the customaryearlier practice. This is particularly true with reference toinner-spring mattresses or box springs for beds Where the supportingsurface is of substantial extent and Where it is desirable that localsagning under load be minimized. This characteristic is especiallydesirable in a box spring which forms a platform for the support of amattress and which is required to provide a substantially horizontalfiat upper surface on which the mattress may rest. The principal objectof the present invention is to provide a spring assembly of suchconstruction that its upper surface remains substantially fiat andhorizontal, even though sustaining a locally applied load.

In spring assemblies as heretofore designed, it has been quite customaryto tie together the upper and lower ends of adjacent spring coils ofeach individual row and it has also been proposed, as in the abovepatent, No. 2,197,131, to tie the upper convolutions of springs ofadjacent rows to each other. Usually, the assembly also comprises arectangular frame, for example of heavy wire, providing an enclosurewithin which the upper ends of the constituent spring coil are arrangedand with a similar frame forming a boundary enclosure for the lower endsof the springs. However, as previously devised, such frames havecontributed but little to the stiffness of the assemblies as a whole asrespects resistance to sagging under load.

In accordance with the present invention, provision is made whereby suchan enclosing frame is utilized as an element of means whereby all of thesprings of a given row are so united, at least at their upper ends, andso supported or suspended that the effect of a locally imposed load isdistributed among a plurality of springs and, at the same time, theeffective resistance to depression of each individual spring isincreased. Thus, the upper surface of the assembly remains substantiallyflat.

In the attainment of this result and assuming that the spring assemblyis of the general type above described and is provided with rectangularframe members, as described, the improved effect, whereby the object ofthe invention is obtained, results from connecting the opposite sidemembers of each frame by strong wires, for example one for each row ofsprings, and wherein each wire is permanently secured, for example, bycoiling one of its ends about one side member of the frame; thenextending it longitudinally of a row of springs; and, while placing itunder substantial tension, attaching its opposite end to the oppositeside member of the frame as by coiling around said end member, so thatsaid wire in the completed assembly is under high tension. This wire isconnected to each of the several springs in the row, desirably at thepoint at which the endmost convolutions of juxtaposed springs are unitedto each other. Since this wire is under initial tension and since it isof material highly resistant to tensile stress, any force tending todepress this wire at any point between its connections to the oppositeside members of the frame is opposed by the resistance of the stiffframe members. Thus a load imposed upon any of the constituent springsof a row is resisted not only by the spring itself but by the stifilyresilient Wire of the surrounding frame and also by the resistance ofall of the springs in a row as transmitted to the suspension wire. Thiswire thus functions according to the same principle as the cable of asuspension bridge. The aforesaid arrangement, although very simple, isvery effective in preventing undesirable local depression of the upperor supporting surface of the assembly. I

Other and further objects and advantages of the invention will bepointed out in the following more detailed description and by referenceto the accompanying drawings wherein:

FIG. 1 is a fragmentary plan view of a spring assembly embodying thepresent invention;

FIG. 2 is a fragmentary vertical section substantially in the lane ofthe line 22 of FIG. 1;

FIG. 3 is a fragmentary elevation looking from the left-hand side ofFIG. 1;

FIG. 4 is a fragmentary plan view, to larger scale, illustrating adesirable way of suspending a pair of juxtaposed spring coils from thetension member of the present invention; and

FIG. 5 is a small scale, diagrammatic plan view of a spring assemblyaccording to this invention.

Referring to the drawings and in particular to FIG. 5, whichdiagrammatically illustrates a spring assembly in accordance with thepresent invention, the numerals 1, 2 and 3 designat coil springsarranged in one transversely extending row, while the numerals 4, 5 and6 designate corresponding springs in the adjacent transversely extendingrow, the several rows of springs being arranged within a frame (FIG. 5)comprising the opposite end members 20 and 26a and the front and rearmembers 20b and 200. This frame may desirably consist of stiff, carbonsteel spring wire of a gauge, for example, of from No. 9 to No. 3(American wire gauge), bent to rectangular form with rounded corners andwith the ends permanently joined, for example at one end of the frame,by welding or soldering. Such a'frame is highly resistant todeformation, as by the deflection of its opposite parallel memberstoward each other. As shown in FIG. 5, which is a plan view, the frame,comprising the members 20, 20a, 20b and 200, is at the top of the springassembly but as illustrated in FIG. 3, the spring assembly comprises abottom frame, desirably like the top frame, the member 21 of this bottomframe corresponding to the member 20 of the frame shown in FIG. 5.According to prior practice, the upper and lower convolutions of thebordering spring coils may be connected to the front and rear members ofthe respective frames by a helical wire coil H (FIG. 1), said borderingcoils thus supporting the frame.

Also in accordance with prior practice, for example as illustrated inthe above patent to Levine, No. 2,197,131, adjacent coils in each row:are connected together at their upper and lower ends while the coils ofadjacent rows are similarly connected to each other. Thus, asillustrated in the patent just referred to, the uppermost convolutionsof the coils of adjacent rows are connected by tie wires 11 of lessergauge than the wires which form the frame, and these tie wires are sodevised as not only to connect coils of adjacent rows but also toprovide the connections between adjacent coils of the same row. Onedesirable mode of connecting the tie wires to the coils is shown in saidpatent. Thus, as shown in FIGS. 2 and 4, a given wire 11 is so bent asto form bights 10a and 10b which embrace the uppermost turns 1x and 2x,respectively, of the adjacent springs 1 and 2, so as to connect thelatter springs, and since the tie wire 11 extends from one side of thespring assembly to the other, it thus serves to connect the coils ofadjacent rows.

In accordance with the present invention, a tensioned suspension wire Thas one end connected to the side member 20 of the frame, as by coilingit about said member and, if desired, by welding or soldering it to themember 20, and extends across the entire width of the assembly and hasits opposite end (FIG. 2) connected to the frame member 20a as bycoiling it about said frame member and, if desired, soldering or weldingit to the latter. Each of the wires T extends along a line defined bythe axes of the several coils of a given row and it is connected to thesprings constituting each pair of adjacent springs in any suitablemanner, desirably with some provision for relative movement of theparts. Conveniently and desirably such connection is made by so bendingthe tie wire 11 so as to-provide the latter with a third bight 11m (FIG.4) through which the suspension wire T passes so that the upperconvolutions lxand 2x of the adjacent springs 1 and 2 for example, aresuspended from the wire. The same connection is provided between thewire T and the upper convolutions of each spring of a pair of adjacentsprings. Desirably, similar tensioned suspension wires T extend acrossth assembly above each row of springs and are connected to the severalcoils of each corresponding row.

In assembling the suspension wires T with the other parts of theassembly and after connecting one end of a given wire T to one of theframe members, the wire T is placed under strong tension and held undertension while it is being connected to the opposite member of the frame.

Sinc the frames are stiff and resist bending, the tension wires arenormally substantially straight and under substantial tension in thecompleted assembly, the frame members to which the ends of the wires aresecured being stiffly resilient, and since these wires T are of hightensile strength and since their opposite ends are anchored to theframe, they strongly resist any force tending to depress them. Since theupper ends of the coils are secured to and in a sense suspended fromthese tensioned wires T, the depression of any given coil or of adjacentcoils by a locally applied downward force is strongly resisted. Thus theentire upper surface of the assembly is maintained approximately fiateven under substantial load. In this simple way such a spring assemblyis greatly improved as respects its ability to maintain a substantiallyfiat, horizontal upper surface even though loaded, although it isresilient, as respects the capability of the entire upper surface of thespring to be pressed down toward the lower surface.

, While the particular means of connecting the suspension wires T to theframe, as well as the specifically described way of connecting the wiresT to adjacent springs has been found desirable, it is to be understoodthat other means of connection, having an equivalent function, are to beconsidered as within the scope of the invention. Furthermore, althoughas here suggested the suspension wires T extend longitudinally of eachrow of spring coils, it is contemplated that they may be omitted, forexample at alternaterows, or if additional resistance be desired, thenthat they may also be arranged between adjacent rows, although in thelatter event they would not be connected directly to any individualspring. However, under such circumstances, it is contemplated that thesuspension wire T might underlie the tie wires thus to give support tothe latter.

It will be understood that in accordance with a preferred embodiment,the lower frame of the assembly will also be provided with wires likethe wires T, for example, as shown at T in FIG. 2. Such an arrangementpermits the assembly to be used with either side up if desired, and alsoprovides a very firm support for the spring assembly so that even thoughit may rest upon a surface which is not exactly horizontal, neverthelessthe assembly as a whole provides a good foundation, for example, forsupporting an inner-spring or other type of mattress.

The suspension wires are of high tensile strength, for example,high-carbon spring steel, desirably of a diameter greater than that ofthe tie wires, but somewhat less than that of the frame. It will benoted that the upper and lower convolutions of each spring areconnected, at diametrically opposite points to one of the suspensionwires, which, by reason of the stiffness of the suspension wire, tendsto prevent tipping of the individual spring and so helps to maintain aflat surface.

While herein the invention has been described with particular referenceto its embodiment in a bed spring, it will be understood that, exceptfor a variation in dimensions, it may be embodied in assemblies for usein seat cushions of large or small size; likewise that the improvedassembly may be used as an open or uncovered spring; or as the resilientelement of a box spring or inner-spring mattress.

While in the drawings the assembly has been illustrated as comprising arelatively small number of coil springs, it is to be understood thatassemblies of any dimension and having any desired number of coils arewithin the purview of the invention.

While a desirable embodiment of the invention has herein beenillustrated and described by way of example, it is to be understood thatthe invention is broadly inclusive of any and all modifications fallingwithin the scope of the appended claims.

I claim:

1. A spring assembly of the kind wherein a plurality of rows of equallength, upright, coiled springs are attached to each other by their topand bottom convolutions, and wherein tie wires, extending transverselyof the several rows, unite corresponding springs of the several rows,and wherein an upper, substantially rectangular, open frame, which ishighly resistant to deformation, surrounds and is substantially coplanarwith the top convolutions of the several springs and is connected to andsupported by the border springs of said assembly, the assembly furthercomprising a substantially rectilinear lower frame to which the lowerconvolutions of the border springs are connected, characterized inhaving means, additional to the springs themselves, comprising a singlesuspension element for each individual row of springs which tends tomaintain the entire upper surface of the assembly, as constituted by thecollective upper convolutions of the constituent springs and the tiewires, fiat and in a horizontal plane.

2. A spring assembly according to claim 1, further characterized in thatthe means tending to maintain the upper surface of the assembly flat andin a horizontal plane comprises tensioned suspension elements connectingopposite parallel sides of the rectangular top frame to each other, saidsuspension elements being of material of a high tensile strength andbeing so connected at their opposite ends to the respective sides of theframe that they are normally under tensile stress, and means connectingthe springs of each row to one of said suspension elements.

3. A spring assembly according to claim 1, further char-. acterized inthat the lower frame is substantially identical in construction with theupper frame and in having suspension wires extending across the assemblybetween opposite side members of the lower frame, each respectivesuspension wire being connected to the lower convolutions of the springsof a corresponding row, and each of said suspension wires of the lowerframe being normally under tension.

4. A spring assembly which comprises a plurality of parallel rows ofjuxtaposed spring coils and wherein the springs in one row aresubstantially aligned with corresponding springs in the next row, andthe juxtaposed springs in one row are tied to the corresponding springsin the next row by tie wires which extend transversely of the severalrows and which connect the juxtaposed springs in the one row to thejuxtaposed springs in the next row, said spring assembly comprisingupper and lower, substantially rectangular open frames, each frame beinghighly resistant to deformation, one frame surrounding and beingsubstantially coplanar with the top convolutions of the several springsand which is connected to the border springs of the assembly, and thelower frame being substantially coplanar with the bottom convolutions ofthe several springs and being connected to the lower convolutions of theborder springs of the assembly, suspension Wires extendinglongitudinally of each row of springs, both at the top and bottom of theassembly, said suspension Wires being under strong tension andconnected, at their opposite ends, to those parallel frame members,respectively, which extend along the opposite ends of the rows of thesprings, each of said tie Wires being substantially straight except forbights protruding at spaced regions thereof, one such bight engaging theend convolution of one coil spring of a pair, another bight engaging theend convolution of the other spring coil of a pair thereby uniting saidconvolutions, and a third bight embracing the tensioned suspension Wireand thereby permanently connecting the suspension wire to said twoadjacent springs.

5. A spring assembly comprising a plurality of rows of equal length,upright, coiled springs, upper and lower substantially rectangular,substantially rigid, open frames, each consisting of high-carbon springsteel wire of a gauge within a range of from 9 to 3 (American WireGauge), means connecting the upper and lower convolutions of adjacentsprings in each row, and means connec ing the upper and lowerconvolutions of juxtaposed springs in adjacent rows, and suspensionwires, each connected, at its opposite ends, to those parallel framemembers, respectively, which extend along the opposite ends of the rowsof springs, each suspension wire being under strong tension andextending along one of the rows of springs, and means connectingdiametrically opposite points of the end convolutions of each spring ofa row to the corresponding suspension Wire.

6. A spring assembly comprising a plurality of rows of equal length,upright, coiled springs, upper and lower substantially rectangular,substantially rigid, open frames, each consisting of high-carbon springsteel wire, means connecting the upper convolutions of adjacent springsin each row, means connecting the lower convolutions of adjacent springsin each row, means connecting the upper convolutions of juxtaposedsprings in adjacent rows, means connecting the lower convolutions ofjuxtaposed springs in adjacent rows, and suspension Wires, eachconnected, at its opposite ends, to those parallel members respectivelyof the upper frame, which extend along the opposite ends of the rows ofsprings, each suspension wire extending along one of the rows ofsprings, and means connecting diametrically opposite points of the endconvolutions of each spring in said row to the suspension wire, thesuspension wires being under strong tension.

7. A spring assembly which comprises a plurality of parallel rows ofjuxtaposed spring coils and wherein the springs in one row aresubstantially aligned with corresponding springs in the next row, andthe juxtaposed springs in one row are tied to the correspondingjuxtaposed springs in the next row by tie wires extending transverselyof the several rows and which connect the juxtaposed springs in the onerow to the juxtaposed springs in the next row, suspension wiresextending longitudinally of each row of springs, both at the top andbottom of the assembly, rneans providing an anchorage for each end,respectively, of each suspension wire, each such wire being under strongtension, each of said tie wires being substantially straight except forbights protruding at spaced regions thereof, one such bight engaging theend convolution of one coil spring of a pair, another bight engaging theend convolution of the other spring coil of a pair thereby uniting saidconvolutions, and a third bight embracing the tensioned suspension wireand thereby permanently connecting the suspension wire to said twoadjacent springs.

References Cited by the Examiner UNITED STATES PATENTS 8,669 1/52 Waters5260 X 803,933 11/05 Smith 5260 X 909,390 1/09 Frank 5277 2,197,131 4/40Levine 5273 2,909,216 10/59 Stern et al 5-266 FRANK B. SHERRY, PrimaryExaminer.

1. A SPRING ASSEMBLY OF THE KIND WHEREIN A PLURALITY OF ROWS OF EQUALLENGTH, UPRIGHT, COILED SPRINGS ARE ATTACHED TO EACH OTHER BY THEIR TOPAND BOTTOM CONVOLUTIONS, AND WHEREIN TIE WIRES, EXTENDING TRANSVERSELYOF THE SEVERAL ROWS, UNIT CORRESPONDING SPRINGS OF THE SEVERAL ROWS, ANDWHEREIN AN UPPER SUBSTANTIALLY RECTANGULAR, OPEN FRAME, WHICH IS HIGHLYRESISTANT TO DEFORMATION, SURROUNDS AND IS SUBSTANTIALLY COPLANAR WITHTHE TOP CONVOLUTIONS OF THE SEVERAL SPRINGS AND IS CONNECTED TO ANDSUPPORTED BY THE BORDER SPRINGS OF SAID ASSEMBLY, THE ASSEMBLKY FURTHERCOMPRISING A SUBSTANTIALLY RECTILINEAR LOWER FRAME TO WHICH THE LOWERCONVOLUTIONS OF THE BORDER SPRINGS ARE CONNECTED, CHARACTERIZED INHAVING MEANS, AD-